16, 24-cyclo-21-norcholene derivatives



United States Patent Ofitice 3,62,850 Fatented Nov, 6, 1962 3,062,850 16,24-CYCLO-21-NORCHOLENE DERIVATIVES Monroe E. Wall, Chapel Hill, NC, and Samuel Serota,

Philadelphia, and Harold E. Kenney, Chalfont, Pa., assignors to the United States of America as represented by the Secretary of Agriculture No Drawing. Filed May 1, 1962, Ser. No. 191,649 16 Claims. (Cl. 260-39745) (Granted under Title 35, US. Code (1952), see. 266) A non-exclusive, irrevocable, royalty-free license in the invention herein described, throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This application is a continuation-in-part of application bearing Serial No. 97,109, filed March 20, 1961, now abandoned.

This invention relates to a novel series of steroids having a 6-membered ring fused to carbon atoms 16 and 17, and process for preparation thereof. These compounds can be regarded as derivatives of 16,24-cyclo-norcholene.

In general according to the present invention compounds of the general formula wherein the fusion of the rings A and B may be a, 55, or A the moiety at C-3 is a or {3, and R is a hydrogen atom or an acyl radical derived from a lower (short carbon chain) fatty acid, are prepared by heating a l2-keto- 16-dehydropregnene with acetone in the presence of a base, and, when R is an acyl radical, acylating the 3-hydroxy compound by conventional procedures.

Novel steroids of this general formula have been demonstrated to have an excitatory effect on the exocrine secretion of the pancreas. The exocrine fluids from the pancreas are a source of enzymes which aid in food digestion and also are a source of chemical means for assisting in control of acidity of the upper intestinal tract.

The reaction appears to apply generally to a 12-ketol6-dehydropregnene. Compounds used as starting materials are steroids such as 3/8-acetoxy-5a,A -pregnene-12, ZO-dione; 3p-acet0xy-5B,A -pregnene-12,20-dione; Sp-acetoxy-A -pregnadiene-l2,20-dione and 3a-acetoxy-5BA pregnene-12,20-dione, or corresponding compounds in which the moiety at the 3-position is a hydroxyl group or an acyloxy group obtained by esterification with a short carbon chain fatty acid.

The presence of the 12-keto group is, however, critical to the invention. Thus, the treatment of 16-dehydropregnenolone with acetone and aqueous potassium hydroxide gave unchanged l6-dehydropregnenolone.

The base may be sodium hydroxide, potassium hydroxide, barium hydroxide, sodium methoxide, potassium butoxide, and similar compounds. The preferred system is acetone and potassium hydroxide.

Heating the reaction mixture at the atmospheric pressure at about the boiling temperature of acetone, a reaction time of one to about five hours is sufficient for high yields of conversion of the 12-keto-l6-dehydropregnene to the 16,24-cyclo derivative. Lower temperatures may be employed for promoting the reaction, in which case heating for longer than five hours is recommended.

Upon addition of water to the reaction mixture the 16,24-cyc1o derivative crystallizes, providing a convenient means of separating this reaction product. It is obvious, however, that other means of separating this product, such as chromatography or partition in solvents can be employed for this purpose.

The preparation of compounds of the present invention is illustrated in Examples 1, 3, 4 and 5. The 3-hydroxy and 3-acyloxy products of these examples are representa tive of the general formula previouly described.

Example 2 demonstrates the hydrogenation of the 22, 23-double bond in the new steroids, and Example 6 shows the oxidation of a 3-hydroxy-A representative of the general formula to the 3-keto-A form which is characteristic of cortisonedike steroids.

Example 1 Preparation of 3fi-acet0xy-23-methyl-5w16,17-cycl0-21- nor-A -ch0lene-12,2O-dione.Five grams of 3,8-acetoxy-5a-A -pregnene-12,20-dione, ml. of acetone, and 8 g. of potassium hydroxide in 50 ml. of water were combined in a flask and heated under reflux conditions (solvent vapors condensed and returned to the flask) for about 5 hours. The mixture was diluted with 100 ml. of water and allowed to stand overnight. A crystalline product, 2.8 g., was separated from the solution and identified as EBB-hydroxy 23 methyl-Sa-l6,24-cyclo-21-nor-A cholene-12,20-dione, M.P. 224-226 C. Upon acetylation by standard procedures, for example, heating with acetic anhydride or acetic anhydride in pyridine, followed by crystallization from methanol there was obtained 2.6 g. of the 3p acetate derivative, M.P. 247.5248.5 C. [a] =+197 (1.5% in CHCI Example 2 Preparation of 3B-acet0xy-23-methyl-5&16,24-cycl0-21- n'0r-A -cholene-12,20-dione.Employing the same general procedure as described in Example 1, but starting with 3,6-acetOXy-S S-A -pregnene-12,20-dione, the reaction gave 3B-hydroxy-23-rnethyl-5fl-16,24-cyclo-21-nor-A cholene-12,20-dione which upon acetylation gave 313-acetoxy-23-methyl-5fl-16,24-cyclo-21-n0rA -cholene-12,20- dione.

Example 4 Preparation of 3a-acetoxy-23-methyl-5&16,24-cycl0-21- nor-A -cholene-12,20-dione.In a manner similar to that of Example 1, the reaction of acetone with 3a-5B-A pregnene-l2,20-dione gave 3a-hydroxy-23-methyl-5B-16, 24-cyclo-2l-nor-A -cholene-12,20-dione which upon acetylation gave 3a-acetoxy-23-methyl-5 8-16,24-cyclo-21- nor-A -cholene-12,20-dione.

Example 5 Preparation of 3/3-acetoxy-23-methyl-16,24-cycl0-21- nor- -ch0ladiene-12,20-di0ne.In a manner similar to that of Example 1, but starting with 3,3-acetoxy- A -pregnadiene-12,20-dione the reaction with acetone in the presence of a base gave 3p-hydroxy-23-methyl-16,24- cyclo 21 nor-A -choladiene-12,20-dione, M.P. 264265 C., [oc] =+147 (1.6% in CHCI Acetylation gave the 3-acetate derivative, M.P. 234-236 C., l ln =+l04 (1.5% in CHCl Example 6 II a I 17 wherein the fusion of the rings A and B is selected from the group consisting of 50:, B, and A R is selected from the group consisting of a hydrogen atom and an acyl radical derived from a short carbon chain saturated fatty acid, and the position of the OR group at C-3 is selected from a and 3.

2. A compound of the general formula of claim 1 in which the fusion of rings A and B is 50:, the position of the -OR group is 36, and R is selected from the group consisting of a hydrogen atom and an acyl radical derived from a short carbon chain saturated fatty acid.

3. 3 3-hydroxy-23methyl-Sa-16,24-cycl0-21nor-A cholene12,20-dione.

4. 3,8-acetoxy-23-methyl-5a-l6,24-cyclo-2l-nor-A cholene-12,20-dione.

5. A compound of the general formula of claim 1 in which the fusion of rings A and B is 56, the position of the OR group is selected from the group consisting of 3a and 3,3, and R is selected from the group consisting of a hydrogen atom and an acyl radical derived from a short chain saturated fatty acid.

6. 3a hydroxy-23-methyl-5fi-16,24-cyclo-21-nor-A cholene-12,20-dione.

7. 3oz acetoxy-23-methyl-5fl-16,24-cyclo-21-nor-A cholene-12,20-dione.

8. 313 hydroxy 23-methyl-5 3-16,24-cyclo-21-nor-A -cholene-12,20-dione.

9. 3B acetoxy 23-methyl-5fi-16,24-cyclo-2I-nor-A -cholene-12,20-dione.

10. 3B acetoxy-23-methyl-5a-16,24-cyclo-21norcholene-12,20-dione.

11. 23 methyl-16,24-cyclo-21-nor-A -choladiene-3,l2,20-trione.

12. A compound of the general formula of claim 1 in which the fusion of the rings A and B is A the position of the OR group is 3 3, and R is selected from the group consisting of a hydrogen atom and an acyl radical derived from a short chain saturated fatty acid.

13. 3,8 hydroxy 23 methyl 16,24 cyclo-2l-nor- A -choladiene-12,20-dione.

14. 3/3 acetoxy 23 methyl 16,24 cyclo21-nor- A -choladiene-12,20-dione.

15. A process comprising heating a 12-keto-16-dehydropregnenc of the general formula *20 23 E u W 0 ID wherein the fusion of the rings A and B is selected from the group consisting of 5a, Sfi, and A and the position of the OH group at C-3 is selected from the group consisting of oz and [3.

16. A process for preparing 23-methyl-16,24-cyclo-21- nor-A -choladiene-3,12,20-trione comprising subjecting 3 3-hydr0xy-23-methyl-16,24-cyclo-21nor-A -choladiene-12,20-dione to the oxidizing action of a sulfuric acid-chromium trioxide mixture-in cold acetone, separating the oxidation product from the reaction mixture, heating the oxidation product in acetone in the presence of p-toluene sulfonic acid to isomerize the oxidation product and separating from the isomerization system 23- methyl-16,24-cyclo-21-nor-A -choladiene-Br,12,20- trione.

No references cited. 

1. A COMPOUND OF THE GENERAL FORMULA 